Docs: Add updated screenshots to kv subkey docs

[hellobontempo]

Description

Preview here.

• Replace screenshot to display the overview card (the original screenshot showed the secret data page, but this data is actually returned from the READ :engine/data/:secret_path endpoint and not the /subkeys one)
• Add enterprise banner, viewing subkeys is an enterprise only feature.
• Add screenshot with the Reveal subkeys toggled on which is the second place in the GUI where subkeys are viewable

TODO only if you're a HashiCorp employee

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  of a public function, even if that change is in a CE file, double check that
  applying the patch for this PR to the ENT repo and running tests doesn't
  break any tests. Sometimes ENT only tests rely on public functions in CE
  files.
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  description. Also, make sure the changelog is in this PR, not in your ENT PR.

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[hellobontempo]

Feel free to revert, but I removed "data" here because "metadata" and "data" are key words in kv v2 and get confused a lot. In this engine it seems helpful to remove data unless we're talking specifically about "secret data" or endpoints that include /data/.

[schavis]

Can you elaborate on the source of the confusion? They may be keywords, but "data" is also an English word that accurately describes the stuff stored in the kv plugin. I'm not against changing things to clarify, but avoiding the word altogether doesn't feel like a reasonable long-term solution.

[hellobontempo]

Sure! I don't mean we should remove the use of data all together, but I think in regards to kv v2 specifically we should be intentional how we use it. Since kv v2 plugins store "secret data" and "metadata," using "data" to encompass both can be confusing.

Most of the time this distinction will probably just be important internally. However, in this context it sounds like users are navigating to secret data, which is not true (anymore). Now the overview page exists as a intermediary layer and clicking a secret path from the list no longer directs users to the "data page."

The overview was added as an additional layer of security so users with read capabilities to :engine/data/:secret_path wouldn't inadvertently read sensitive secret values when clicking into a secret path. So while the overview technically contains data about the secret, the "data" distinction is important here so we're clear it's not secret data.

Happy to discuss over zoom if that's easier 😄

[hellobontempo]

Now that the kv engine includes an "overview" page, some actions require navigating to the "Secrets" tab while others can be done from the overview. I updated the various sub-steps to include or not include this step accordingly, but let me know if this should be reverted!